1. Field of the Invention
This invention relates generally to pipe cleaning machines and more particularly to a power driven machine for storing and rotatively feeding and retracting flexible plumbers snakes or springs formed of helically wound spring wire.
2. Description of the Prior Art
Numerous types of motorized tools have been suggested for use in clearing sewer lines of obstructions. Over the years the construction of these tools has become standardized in many respects. For example, such apparatus typically includes a closed drum, or reel, from which a length of flexible, helically wound spring, known as a plumbers snake, is paid out. After coming off the reel, the spring is guided into a forwardly disposed guide element which is substantially in alignment with the axis of the reel. If the snake is not to be paid out by hand, the guide element is usually provided with means such as rollers, jaws, or the like which engage the snake so that upon rotation of the drum, or reel, rectilinear movement is imparted to the snake. Thus, if the reel is rotated in one direction, the snake is paid out; while if it is rotated in the opposite direction, it is taken in.
In cleaning out a clogged sewer line the free end of the snake is first introduced into the line. next, rotation of the drum in a forward direction is initiated and finally the snake is paid out by hand or the feed means is brought into engagement with the snake so as to feed it into the line. Feeding of the snake is continued until the obstruction is encountered and loosened. However, should the snake encounter a blockage within the line which cannot be loosened, the snake may be caught so that it cannot rotate. In this situation continued rotation of the reel, even for a short period, will cause significant build-up of torque forces on the snake within the drum. If feeding is allowed to continue, these torque forces will cause undesirable back-looping and kinking of the snake within the storage drum or reel. This back-looping in turn causes the snake to become tangled within the drum or reel so that the snake can sometimes neither be paid out or taken in. To rectify this situation the operator must stop the cleanout operation and somehow relieve the torque build-up so that the snake can be untangled. This operation can be both dangerous and time consuming and frequently the operator is simply unable to clear the entanglement sufficiently to continue. It is this problem of torque build-up and back-looping of the snake within the drum which is addressed by the present invention.
In the past, various arrangements have been suggested to eliminate or minimize the torque build-up and back-looping problem inherent in most motorized sewer clean-out tools. One of the most successful of these was made by the present inventor and is described in U.S. Pat. No. 3,958,293. Another proposed solution to the problem is described in U.S. Pat. No. 3,095,592 issued to Robert G. Hunt. The Hunt machine embodied an independently rotatable, combination torque reaction element and guide tube which extended into the storage reel from the front of the machine and cooperated therewith to guide the spring into and out of the storage reel and to prevent kinking thereof due to torque build-up. The apparatus described in the earlier patent issued to the present inventor improved upon the Hunt concept by providing an independently rotatable, uniquely grooved, torque reaction element which extended into the reel and cooperated with the reel to prevent the snake from kinking or back-looping.
The apparatus of the present invention represents a significant improvement over both the Hunt apparatus and the apparatus described in U.S. Pat. No. 3,958,293. As will become apparent from the description which follows, the back-looping and snake tangling problem has been uniquely overcome in the apparatus of the present invention through a novel redesign of the configuration of the storage drum itself. This simple, but highly effective solution to this longstanding problem effectively prevents the tangling of the snake within the drum by controllably guiding the snake into a restricted volume storage portion of the drum through a strategically placed passageway formed by necking down the drum at a location proximate the periphery thereof. With this novel construction, the snake can be smoothly withdrawn from its coiled configuration and, because of the restricted storage volume coupled with the size and location of the passageway leading to the storage volume, the snake is prevented from back-looping and tangling up within the storage area even upon being subjected to substantial torque inducing forces.